submodule(fffc_linalg) fffc_linalg_eye
contains

    module procedure eye
    integer :: i, j

    do j = 1, n
        do i = 1, m
            if (i == j) then
                a(i, j) = 1_int8
            else
                a(i, j) = 0_int8
            end if
        end do
    end do

    end procedure eye

end submodule fffc_linalg_eye
